https://teaching.ncl.ac.uk/bms/wiki/index.php?title=Special:Contributions/120240883&feed=atom&deletedOnly=&limit=50&target=120240883&topOnly=&year=&month=The School of Biomedical Sciences Wiki - User contributions [en]2019-09-15T10:36:23ZFrom The School of Biomedical Sciences WikiMediaWiki 1.17.0https://teaching.ncl.ac.uk/bms/wiki/index.php/Integral_and_peripheral_membrane_proteinsIntegral and peripheral membrane proteins2013-10-20T10:58:08Z<p>120240883: </p>
<hr />
<div>=== Integral Membrane Proteins ===<br />
<br />
These are [[Proteins|proteins]] directly linked to the [[Plasma membrane|plasma membrane]] of [[Cells|cells]];&amp;nbsp;they do not have intermediate [[Molecules|molecules]] between them and the [[Plasma membranes|plasma membranes]]. They are also considered as proteins that fully pass through the membrane ([[Carrier protein|carrier proteins]] and [[Channel protein|channel proteins]]). <br />
<br />
=== Peripheral Membrane Proteins ===<br />
<br />
These proteins are connected to the plasma membrane through intermediate [[Molecules|molecules]] (even integral proteins) by noncovalent interactions or proteins attached to only one side of the membrane; do not pass through the membrane &lt;ref&gt;Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; 2002&lt;/ref&gt;.&lt;br&gt; <br />
<br />
=== Reference ===<br />
<br />
&lt;references /&gt;</div>120240883https://teaching.ncl.ac.uk/bms/wiki/index.php/Integral_and_peripheral_membrane_proteinsIntegral and peripheral membrane proteins2013-10-17T18:35:25Z<p>120240883: Peripheral membrane proeins bind integral proeins by noncovalent interactions</p>
<hr />
<div>'''Integral Membrane Proteins''' <br />
<br />
These are [[Proteins|proteins]] directly linked to the [[Plasma membrane|plasma membrane]] of [[Cells|cells]];&amp;nbsp;they do not have intermediate [[Molecules|molecules]] between them and the plasma membranes. They are also considered as proteins that fully pass through the membrane ([[Carrier protein|carrier proteins]] and [[Channel protein|channel proteins]]). <br />
<br />
'''Peripheral Membrane Proteins''' <br />
<br />
These proteins are connected to the plasma membrane through intermediate molecules (even integral proteins) or proteins attached to only one side of the membrane; do not pass through the membrane &lt;ref&gt;Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; 2002&lt;/ref&gt;.&lt;br&gt; <br />
<br />
&lt;h3&gt; Reference &lt;/h3&gt;<br />
&lt;p&gt;&amp;lt;span class=&quot;fck_mw_references&quot; _fck_mw_customtag=&quot;true&quot; _fck_mw_tagname=&quot;references&quot; /&amp;gt;<br />
&lt;/p&gt;</div>120240883https://teaching.ncl.ac.uk/bms/wiki/index.php/DNADNA2012-11-30T13:54:10Z<p>120240883: </p>
<hr />
<div>[[Image:BASE PAIRINGS.png|left|DNA Helix]] <br />
<br />
DNA (deoxyribonucleic acid) is the genetic information found in the [[Nucleus|nuclei]] of most [[Organism|organisms]]. It is arranged into structures called [[Chromosome|chromosomes]].&amp;nbsp;The structure of DNA was first identified as having a 'double-helix' structure by [[Watson|Watson]] and [[Crick|Crick]] in 1953. DNA is composed of 4 [[Base|bases]]:&amp;nbsp;the [[Purine|purines]]:&amp;nbsp;[[Adenine|adenine]]&amp;nbsp;(A) and [[Guanine|guanine]]&amp;nbsp;(G); and the [[Pyrimidine|pyrimidines]]: [[Thymine|thymine]]&amp;nbsp;(T) and [[Cytosine|cytosine]]&amp;nbsp;(C) &lt;ref&gt;HARTL AND JONES,2009:41, GENETICS : ANALYSIS OF GENES AND GENOMES SEVENTH EDITION.&lt;/ref&gt;. These form complementary base pairs of AT and GC. DNA also contains a [[Phosphates|phosphate]] group connected to a [[Deoxyribose sugar|deoxyribose sugar]]. The phosphate group is attached to the sugar through a&amp;nbsp;[[Phosphodiester bond]]. &amp;nbsp; <br />
<br />
=== Structure of DNA ===<br />
<br />
DNA strands are primarily composed of three repeating units: a&amp;nbsp;[[Deoxyribose|2` deoxyribose sugar]]&amp;nbsp;(A five ([[Pentose|pentose]])&amp;nbsp;[[Carbon|carbon]] sugar &amp;nbsp;similar to that of [[Ribose|ribose]] sugar&amp;nbsp;found&amp;nbsp;in [[RNA|RNA]]. Its chemical formula is C&lt;sub&gt;5&lt;/sub&gt;H&lt;sub&gt;10&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt;),&amp;nbsp;a&amp;nbsp;[[Phosphate group|phosphate group]]&amp;nbsp;(contains one [[Phosphorus|phosphorus]] [[Atom|atom]], bonded to 4 [[Oxygen|oxygens]]&amp;nbsp;and forms a [[Phosphodiester bond|phosphodiester bond]], which connects 2 [[Deoxyribose|deoxyribose sugars]] together resulting in the formation&amp;nbsp;of a chain) and a base (one from A, C, G or T, which&amp;nbsp;forms a side chain branching from the 2` deoxyribose sugar). <br />
<br />
The 2` deoxyribose sugar/phosphate group region is regarded as the 'backbone' of DNA strands due to its structural purpose, and the sequence of bases carries the gentic information. In order to produce a double stranded DNA structure, interactions occur between complementary bases. The complementary base pairs in DNA interact with one another via [[Hydrogen bonds|hydrogen bonds]]: A-T interactions consist of 2 intermolecular [[Hydrogen bonds|hydrogen bonds]], whereas&amp;nbsp;G-C interactions consist of 3 intermolecular [[Hydrogen bonds|hydrogen bonds]].&amp;nbsp;These interactions form bridges between two DNA chains, thus creating a double stranded 'ladder' shaped structure. Each strand acts as a template for the other one in DNA replication. DNA is copied into [[MRNA|mRNA]] (messenger RNA) which carries the information from the original DNA template strand to be involved in protein synthesis. &amp;nbsp;The process of DNA being copied into mRNA is termed&amp;nbsp;[[Transcription]]&amp;nbsp; <br />
<br />
Despite many other theories, in 1953 [[James watson|James&amp;nbsp;Watson]] and Frances Crick discovered the true structure of a double&amp;nbsp;stranded DNA&amp;nbsp;molecule to be a 'Double Helix'. This was solved as a result of 'stick-and-ball'&amp;nbsp;models they created,&amp;nbsp;along with utilising the work of fellow scientists [[Rosalind Franklin|Rosalind Franklin]] and [[Maurice Wilkins|Maurice Wilkins]] on [[X-ray crystallography|X-ray crystallography]]&lt;ref&gt;http://nobelprize.org/educational/medicine/dna_double_helix/readmore.html&lt;/ref&gt; . The&amp;nbsp;[[X-ray diffraction|X-ray diffraction]] photographs obtained from [[DNA|DNA]] fibres, displayed a unique X-shape, which illustrates a helical stucture, although they indicated a repeating structure of 3.4 Å apart per turn of the helix, each base is roated 36 degrees from the next one. The diameter of the helix is 20Â. They found that the sugar-phosphate backbone was on the outside and the bases are positioned on the inside of the helix&amp;nbsp;&lt;ref&gt;http://www.chm.bris.ac.uk/motm/dna/dna.htm&lt;/ref&gt;&lt;ref&gt;J.Berg, J.Tymoczko, L.Stryer;, 113-115, 2012 Freeman; Biochemistry&lt;/ref&gt;.&lt;br&gt;<br />
<br />
The DNA of the Indian muntjac which is an Asiatic deer has the longest length ( approximately 3 billion nucleotides) among all the known DNA molecules of other organisms.&lt;ref name=&quot;null&quot;&gt;Berg, J.M, Biochemistry, 7th ed, 2012:117&lt;/ref&gt; <br />
<br />
=== References ===<br />
<br />
&lt;references /&gt;&lt;br&gt;</div>120240883https://teaching.ncl.ac.uk/bms/wiki/index.php/DNADNA2012-11-30T13:52:39Z<p>120240883: </p>
<hr />
<div>[[Image:BASE PAIRINGS.png|left|DNA Helix]] <br />
<br />
DNA (deoxyribonucleic acid) is the genetic information found in the [[Nucleus|nuclei]] of most [[Organism|organisms]]. It is arranged into structures called [[Chromosome|chromosomes]].&amp;nbsp;The structure of DNA was first identified as having a 'double-helix' structure by [[Watson|Watson]] and [[Crick|Crick]] in 1953. DNA is composed of 4 [[Base|bases]]:&amp;nbsp;the [[Purine|purines]]:&amp;nbsp;[[Adenine|adenine]]&amp;nbsp;(A) and [[Guanine|guanine]]&amp;nbsp;(G); and the [[Pyrimidine|pyrimidines]]: [[Thymine|thymine]]&amp;nbsp;(T) and [[Cytosine|cytosine]]&amp;nbsp;(C) &lt;ref&gt;HARTL AND JONES,2009:41, GENETICS : ANALYSIS OF GENES AND GENOMES SEVENTH EDITION.&lt;/ref&gt;. These form complementary base pairs of AT and GC. DNA also contains a [[Phosphates|phosphate]] group connected to a [[Deoxyribose sugar|deoxyribose sugar]]. The phosphate group is attached to the sugar through a&amp;nbsp;[[Phosphodiester bond]]. &amp;nbsp; <br />
<br />
=== Structure of DNA ===<br />
<br />
DNA strands are primarily composed of three repeating units: a&amp;nbsp;[[Deoxyribose|2` deoxyribose sugar]]&amp;nbsp;(A five ([[Pentose|pentose]])&amp;nbsp;[[Carbon|carbon]] sugar &amp;nbsp;similar to that of [[Ribose|ribose]] sugar&amp;nbsp;found&amp;nbsp;in [[RNA|RNA]]. Its chemical formula is C&lt;sub&gt;5&lt;/sub&gt;H&lt;sub&gt;10&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt;),&amp;nbsp;a&amp;nbsp;[[Phosphate group|phosphate group]]&amp;nbsp;(contains one [[Phosphorus|phosphorus]] [[Atom|atom]], bonded to 4 [[Oxygen|oxygens]]&amp;nbsp;and forms a [[Phosphodiester bond|phosphodiester bond]], which connects 2 [[Deoxyribose|deoxyribose sugars]] together resulting in the formation&amp;nbsp;of a chain) and a base (one from A, C, G or T, which&amp;nbsp;forms a side chain branching from the 2` deoxyribose sugar). <br />
<br />
The 2` deoxyribose sugar/phosphate group region is regarded as the 'backbone' of DNA strands due to its structural purpose, and the sequence of bases carries the gentic information. In order to produce a double stranded DNA structure, interactions occur between complementary bases. The complementary base pairs in DNA interact with one another via [[Hydrogen bonds|hydrogen bonds]]: A-T interactions consist of 2 intermolecular [[Hydrogen bonds|hydrogen bonds]], whereas&amp;nbsp;G-C interactions consist of 3 intermolecular [[Hydrogen bonds|hydrogen bonds]].&amp;nbsp;These interactions form bridges between two DNA chains, thus creating a double stranded 'ladder' shaped structure. Each strand acts as a template for the other one in DNA replication. DNA is copied into [[MRNA|mRNA]] (messenger RNA) which carries the information from the original DNA template strand to be involved in protein synthesis. &amp;nbsp;The process of DNA being copied into mRNA is termed&amp;nbsp;[[Transcription]]&amp;nbsp; <br />
<br />
Despite many other theories, in 1953 [[James watson|James&amp;nbsp;Watson]] and Frances Crick discovered the true structure of a double&amp;nbsp;stranded DNA&amp;nbsp;molecule to be a 'Double Helix'. This was solved as a result of 'stick-and-ball'&amp;nbsp;models they created,&amp;nbsp;along with utilising the work of fellow scientists [[Rosalind Franklin|Rosalind Franklin]] and [[Maurice Wilkins|Maurice Wilkins]] on [[X-ray crystallography|X-ray crystallography]]&lt;ref&gt;http://nobelprize.org/educational/medicine/dna_double_helix/readmore.html&lt;/ref&gt; . The&amp;nbsp;[[X-ray diffraction|X-ray diffraction]] photographs obtained from [[DNA|DNA]] fibres, displayed a unique X-shape, which illustrates a helical stucture, although they indicated a repeating structure of 3.4 Å apart per turn of the helix, each base is roated 36 degrees from the next one. The diameter of the helix is 20Â. They found that the sugar-phosphate backbone was on the outside and the bases are positioned on the inside of the helix&amp;nbsp;&lt;ref&gt;http://www.chm.bris.ac.uk/motm/dna/dna.htm&lt;/ref&gt;&lt;ref&gt;J.Berg, J.Tymoczko, L.Stryer;, 113-115, 2012 Freeman; Biochemistry&lt;/ref&gt;.&lt;br&gt;<br />
<br />
The DNA of the Indian muntjac which is an Asiatic deer has the longest length ( approximately 3 billion nucleotides) among all the known DNA molecules of other organisms.&lt;ref&gt;Berg, J.M, Biochemistry, 7th ed, P117&lt;/ref&gt;<br />
<br />
=== References ===<br />
<br />
&lt;references /&gt;&lt;br&gt;</div>120240883